U.S. patent application number 15/769576 was filed with the patent office on 2018-11-01 for parking support method and parking support device.
The applicant listed for this patent is Nissan Motor Co., Ltd.. Invention is credited to Yasuhisa Hayakawa.
Application Number | 20180315312 15/769576 |
Document ID | / |
Family ID | 58556880 |
Filed Date | 2018-11-01 |
United States Patent
Application |
20180315312 |
Kind Code |
A1 |
Hayakawa; Yasuhisa |
November 1, 2018 |
Parking Support Method and Parking Support Device
Abstract
A parking assist method for assisting parking of a subject
vehicle uses a parking assist apparatus comprising a controller and
a display. The controller guides the subject vehicle to a parking
space. The parking assist method includes detecting available
parking spaces into which the subject vehicle can be parked,
setting a parking space suitable for parking of the subject vehicle
among the detected plurality of available parking spaces as a
recommended available parking space in accordance with the
traveling state of the subject vehicle, displaying the recommended
available parking space on the display, setting the recommended
available parking space displayed on the display as a target
parking space for the subject vehicle on the basis of an operation
by a driver or passenger, and performing automated control of the
subject vehicle to park the subject vehicle into the target parking
space.
Inventors: |
Hayakawa; Yasuhisa;
(Kanagawa, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Nissan Motor Co., Ltd. |
Yokohama-shi, Kanagawa |
|
JP |
|
|
Family ID: |
58556880 |
Appl. No.: |
15/769576 |
Filed: |
October 22, 2015 |
PCT Filed: |
October 22, 2015 |
PCT NO: |
PCT/JP2015/079888 |
371 Date: |
April 19, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B60W 30/06 20130101;
B60W 2420/42 20130101; G08G 1/143 20130101; G08G 1/14 20130101;
B60R 21/00 20130101; B60W 2050/146 20130101; B62D 15/0285
20130101 |
International
Class: |
G08G 1/14 20060101
G08G001/14; B60W 30/06 20060101 B60W030/06 |
Claims
1-15 (canceled)
16. A parking assist method for assisting parking of a subject
vehicle using a parking assist apparatus comprising a controller
that guides the subject vehicle to a parking space and a display
that displays parking spaces, the parking assist method comprising:
specifying available parking spaces into which the subject vehicle
can be parked; detecting an available parking space suitable for
parking of the subject vehicle from among the specified available
parking spaces in accordance with a traveling state of the subject
vehicle; setting the detected available parking space as a
recommended available parking space; and when the recommended
available parking space is displayed in a state in which the
subject vehicle decelerates during detection of the recommended
available parking space, prohibiting the recommended available
parking space from changing to another available parking space.
17. A parking assist method for assisting parking of a subject
vehicle using a parking assist apparatus comprising a controller
that guides the subject vehicle to a parking space and a display
that displays parking spaces, the parking assist method comprising:
specifying available parking spaces into which the subject vehicle
can be parked; when parking spaces are present at right and left
with respect to a travel direction of the subject vehicle, setting
one of right and left regions to a settable region for the
recommended available parking space in accordance with a traveling
state of the subject vehicle; setting the parking space included in
the settable region to a recommended available parking space; and
displaying the recommended available parking space on the
display.
18. The parking assist method according to claim 17, comprising
calculating a lateral distance that is a distance from the parking
space located on a side of the subject vehicle to the subject
vehicle, wherein one of the right and left regions is set as the
settable region for the recommended available parking space in
accordance with a length of the lateral distance, and a
characteristic when one of the right and left regions is selected
is a hysteresis characteristic with respect to the length of the
lateral distance.
19. A parking assist method for assisting parking of a subject
vehicle using a parking assist apparatus comprising a controller
that guides the subject vehicle to a parking space and a display
that displays parking spaces, the parking assist method comprising:
specifying available parking spaces into which the subject vehicle
can be parked; setting the available parking space located at one
of right and left to the recommended available parking space in
accordance with a traveling situation of the subject vehicle when a
predetermined number or more of the available parking spaces are
present and; displaying the recommended available parking space on
the display.
20. The parking assist method according to claim 17, comprising
estimating an intention of a driver or passenger of the subject
vehicle in accordance with a traveling state of the subject
vehicle; wherein the recommended available parking space is set
among the specified available parking spaces in accordance with the
intention of the driver or passenger.
21. The parking assist method according to claim 20 wherein the
intention of the driver or passenger is estimated on an assumption
that the traveling state is represented by at least one of a
traveling position of the subject vehicle and a vehicle speed of
the subject vehicle.
22. The parking assist method according to claim 17, comprising:
setting the recommended available parking space displayed on the
display to the target parking space for the subject vehicle on a
basis of an operation by a driver or passenger of the subject
vehicle; and performing automated control of the subject vehicle to
park the subject vehicle into a target parking space.
23. The parking assist method according to claim 17, comprising
calculating a required time each of the available parking spaces,
the required time being a time required for parking when the
subject vehicle is parked, wherein the available parking space with
which the required time for parking is shorter than a predetermined
time is set as the recommended available parking space.
24. The parking assist method according to claim 17, comprising
calculating a required time each of the available parking spaces,
the required time being a time required for parking when the
subject vehicle is parked, wherein the available parking space with
which the required time for parking is shortest is set as the
recommended available parking space.
25. The parking assist method according to claim 17, comprising
specifying a gaze point which is separated from the subject vehicle
by a given gaze point distance, wherein the available parking space
with which a distance from the gaze point to the available parking
space is shorter than a predetermined distance threshold is set as
the recommended available parking space.
26. The parking assist method according to claim 17, comprising
specifying a gaze point which is separated from the subject vehicle
by a given gaze point distance, wherein the available parking space
with which a distance from the gaze point to the available parking
space is shortest is set as the recommended available parking
space.
27. The parking assist method according to claim 17, comprising
evaluating ease of entry when the subject vehicle is parked into
each of the available parking spaces, wherein the available parking
space into which entry is easiest is set as the recommended
available parking space.
28. The parking assist method according to claim 25, wherein a
length of the gaze point distance is set in accordance with whether
a travel direction of the subject vehicle is forward or
backward.
29. A parking assist apparatus comprising: a display configured to
display parking spaces; and a controller configured to guide the
subject vehicle to a parking space, wherein the controller: specify
available parking spaces into which the subject vehicle can be
parked; detect an available parking space suitable for parking of
the subject vehicle from among the specified available parking
spaces in accordance with a traveling state of the subject vehicle;
set the detected available parking space as a recommended available
parking space; control the display to display the recommended
available parking space; when the recommended available parking
space is displayed in a state in which the subject vehicle
decelerates during detection of the recommended available parking
space, prohibit the recommended available parking space from
changing to another available parking space; set the recommended
available parking space displayed on the display as a target
parking space for the subject vehicle on a basis of an operation by
a driver or passenger of the subject vehicle; and perform automated
control of the subject vehicle to park the subject vehicle into the
target parking space.
Description
TECHNICAL FIELD
[0001] The present invention relates to a parking assist method and
a parking assist apparatus.
BACKGROUND
[0002] Heretofore, a parking space recognition apparatus has been
known as below. The parking space recognition apparatus detects
spaces into which a subject vehicle can spatially enter, prioritize
the spaces on the basis of preregistered unique information of the
subject vehicle and/or the driver, and outputs a candidate parking
space (see Japanese Patent Application JP2009-205191A).
[0003] However, when attribute information of the subject vehicle
or the unique information of the driver is not registered, an
appropriate parking space cannot be presented to the driver and
passengers.
[0004] A problem to be solved by the present invention is to
provide a parking assist method or a parking assist apparatus with
which an appropriate parking space can be presented to the driver
and passengers.
SUMMARY
[0005] The present invention solves the above problem through
setting a parking space suitable for parking of a subject vehicle
among detected available parking spaces as a recommended available
parking space in accordance with the traveling state of the subject
vehicle, displaying the recommended available parking space on a
display, setting the recommended available parking space displayed
on the display as a target parking space for the subject vehicle on
the basis of an operation by a driver or passenger, and performing
automated control of the subject vehicle to park the subject
vehicle into the target parking space.
[0006] The present invention has an effect that an appropriate
available parking space can be presented to the driver and
passengers because the recommended available parking space suitable
for parking is displayed on the display while setting the
recommended available parking space among the available parking
spaces so that it matches estimation of the vehicle's behavior.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a block diagram illustrating an example of a
parking assist system according to one or more embodiments of the
present invention;
[0008] FIG. 2 is a flowchart illustrating an example of a control
procedure in the parking assist system according to one or more
embodiments of the present invention;
[0009] FIG. 3 is a view illustrating an example of positions at
which on-board cameras are arranged according to one or more
embodiments of the present invention;
[0010] FIG. 4A is a first view for describing an example of a
parking assist process according to an embodiment of the present
invention;
[0011] FIG. 4B is a second view for describing an example of the
parking assist process according to the embodiment;
[0012] FIG. 4C is a third view for describing an example of the
parking assist process according to the embodiment;
[0013] FIG. 4D is a fourth view for describing an example of the
parking assist process according to the embodiment;
[0014] FIG. 4E is a view for describing an example of the parking
assist process according to the embodiment;
[0015] FIG. 4F is a view for describing an example of the parking
assist process according to the embodiment;
[0016] FIG. 5 is a graph illustrating the relationship between a
vehicle speed (V [km]) and a gaze point distance (Y [m]);
[0017] FIGS. 6A-6C are a set of views illustrating examples of
parking patterns to which the parking assist process according to
the embodiment is applied;
[0018] FIG. 7A is a first view for describing an example of a
display screen in the parking assist process according to the
embodiment;
[0019] FIG. 7B is a second view for describing an example of a
display screen in the parking assist process according to the
embodiment;
[0020] FIG. 7C is a third view for describing an example of a
display screen in the parking assist process according to the
embodiment;
[0021] FIG. 7D is a fourth view for describing an example of a
display screen in the parking assist process according to the
embodiment;
[0022] FIG. 7E is a view for describing an example of a display
screen in the parking assist process according to the
embodiment;
[0023] FIGS. 8A and 8B are a set of views for describing an example
of a parking assist process according to another embodiment of the
present invention; and
[0024] FIG. 9 is a graph illustrating the relationship between a
vehicle speed (V [km]) and a gaze point distance (Y [m]).
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0025] Hereinafter, embodiments of the present invention will be
described with reference to the drawings.
First Embodiment
[0026] In this embodiment, the present invention will be described
with reference to an example in which the parking assist apparatus
according to the present invention is applied to a parking assist
system equipped in a vehicle. The parking assist apparatus may also
be applied to a portable terminal device (equipment such as
smartphone and PDA) capable of exchanging information with onboard
devices. The method of displaying parking assist information
according to the present invention can be used in a parking assist
apparatus. Parking assist information relating to the invention of
the displaying method is specifically displayed using a display
21.
[0027] FIG. 1 is a block diagram of a parking assist system 1000
having a parking assist apparatus 100 according to one or more
embodiments of the present invention. The parking assist system
1000 according to the present embodiment assists an operation of
moving (parking) a subject vehicle into a parking space. The
parking assist system 1000 according to the present embodiment
includes cameras 1a to 1d, an image processing device 2, a ranging
device 3, the parking assist apparatus 100, a vehicle controller
30, a drive system 40, a steering angle sensor 50, and a vehicle
speed sensor 60. The parking assist apparatus 100 according to the
present embodiment includes a control device 10 and an output
device 20. The output device includes a display 21, a speaker 22,
and a lamp 23. These components are connected to one another via a
controller area network (CAN) or other in-vehicle LAN to mutually
exchange information.
[0028] The control device 10 of the parking assist apparatus 100
according to the present embodiment is a specific computer
comprising a ROM 12 that stores a parking assist program, a CPU as
an operation circuit that executes the program stored in the ROM 12
to serve as the parking assist apparatus 100 according to the
present embodiment, and a RAM 13 that serves as an accessible
storage device.
[0029] The parking assist program according to the present
embodiment is a program for execution of a control procedure of
presenting parking spaces, into which parking is possible, on the
display 21 and assisting an operation to park the subject vehicle
into a parking space set by a user. The parking assist apparatus
100 according to the present embodiment can be applied to automated
parking in which all of the steering, accelerator, and brake are
automatically operated thereby to park a vehicle automatically and
can also be applied to semiautomated parking in which at least one
operation of the steering, accelerator, and brake is manually
performed and other operations are automatically performed for
parking. In addition or alternatively, the parking assist apparatus
100 can be applied to a parking assist function with which a route
to a parking space is presented to the user and the user operates
the steering, accelerator, and brake to park the vehicle.
[0030] The control device 10 of the parking assist apparatus 100
according to the present embodiment has functions of executing an
information acquisition process, an available parking space
detection process, a recommended available parking space detection
process, and a display control process. Each of the above processes
is executed by cooperation of software for implementing the process
and the above-described hardware.
[0031] FIG. 2 is a flowchart illustrating a control procedure of
the parking assist process executed by the parking assist system
1000 according to the present embodiment. The trigger for starting
the parking assist process is not particularly limited, and the
parking assist process may be triggered by the operation of a start
switch of the parking assist apparatus 100.
[0032] The parking assist apparatus 100 according to the present
embodiment has a function for automatically moving the subject
vehicle to the parking space. In this process according to the
present embodiment, a momentary-type switch such as a deadman
switch is used. In the parking assist apparatus 100, the automated
driving of the subject vehicle is executed when the deadman switch
is pressed and the automated driving of the subject vehicle is
suspended when the pressing of the deadman switch is released.
[0033] Specifically, in step 101, the control device 10 of the
parking assist apparatus 100 according to the present embodiment
acquires images captured by the cameras 1a to 1d attached to
multiple sites of the subject vehicle. The cameras 1a to 1d capture
images of boundary lines of parking spaces around the subject
vehicle and objects existing around the parking spaces. The cameras
1a to 1d may be CCD cameras, infrared cameras, or other appropriate
imaging devices. The ranging device 3 may be provided at the same
position as any of the cameras 1a to 1d or may also be provided at
a different position. The ranging device 3 may be a radar device,
such as a millimeter-wave radar, laser radar and ultrasonic radar,
or a sonar. The ranging device 3 detects the presence or absence of
objects, positions of the objects, and distances to the objects on
the basis of the received signal of the radar device. Such objects
correspond to obstacles, pedestrian, and other vehicles around the
vehicle. The received signal is used to determine whether or not
the parking space is empty (whether or not a vehicle is parked in
the parking space). Obstacles may be detected using the motion
stereo technique by the cameras 1a to 1d.
[0034] FIG. 3 is a view illustrating an exemplary arrangement of
the cameras 1a to 1d disposed on the subject vehicle. In the
example illustrated in FIG. 3, the camera 1a is disposed on the
front grille part of the subject vehicle, the camera 1d is disposed
in the vicinity of the rear bumper, and the cameras 1b and 1c are
disposed on the lower parts of the right and left door mirrors. The
cameras 1a to 1d may each be a camera having a wide-angle lens with
a wide view angle.
[0035] In step 101, the control device 10 also acquires ranging
signals from the ranging device 3, which may be a plurality of
modules attached to multiple sites of the subject vehicle.
[0036] In step 102, the control device 10 of the parking assist
apparatus 100 controls the image processing device 2 to generate an
overhead image. On the basis of the acquired plurality of captured
images, the image processing device 2 generates an overhead image
in which the surrounding state including the subject vehicle and
the parking space for the subject vehicle to park is viewed from a
virtual viewpoint P (see FIG. 3) above the subject vehicle. The
image processing performed by the image processing device 2 may be
conducted, for example, using a method as disclosed in "Development
of Around View System, Proceedings of Society of JSAE Annual
Congress, 116-07 (October 2007), pp. 17-22, SUZUKI Masayasu,
CHINOMI Satoshi, TAKANO Teruhisa." Examples of a generated overhead
image 21A are illustrated in FIGS. 7A and 7B, which will be
described later. These figures each illustrate a display example
that simultaneously displays the overhead image (top view) 21A
around the subject vehicle and a monitoring image (normal view) 21B
around the subject vehicle.
[0037] In step 103, available parking spaces Me are detected. The
control device 10 detects the available parking spaces Me on the
basis of the images captured by the cameras 1a to 1d and/or the
data received by the ranging device 3. The control device 10 stores
a "parking possible condition" for extracting the available parking
spaces Me. The "parking possible condition" is defined from the
viewpoint of extracting a parking space into which parking is
possible. The "parking possible condition" is preferably defined
from the viewpoint of the distance from the subject vehicle, the
viewpoint as to whether or not other vehicles are parked, and the
viewpoint of presence or absence of obstacles. On the basis of the
"parking possible condition," the control device 10 detects the
available parking spaces Me into which the subject vehicle can be
parked. The available parking spaces Me are parking spaces into
which the subject vehicle can be parked. The control device 10
detects the available parking spaces Me on the basis of the images
captured by the cameras 1a to 1d and/or the data received by the
ranging device 3. In the above description, images of available
parking spaces are captured by the on-board cameras and the
available parking spaces Me are detected from the captured images,
but information may be acquired from an external server and the
available parking spaces may be specified from the acquired
information.
[0038] A method of detecting the available parking spaces Me will
be described below. The control device 10 determines whether or not
the subject vehicle is traveling in an area that includes parking
spaces (such an area will also be referred to as a "parking area,"
hereinafter), on the basis of the vehicle speed or positional
information from a navigation system (not illustrated). For
example, when the vehicle speed of the subject vehicle is a
predetermined vehicle speed threshold or less and this state
continues for a predetermined time or more, the control device 10
determines that the subject vehicle is traveling in a parking area.
In addition or alternatively, when the detected positional
information has an attribute that represents a parking area such as
an area including parking spaces of a highway, for example, the
control device 10 determines that the subject vehicle is traveling
in the parking area. In the present embodiment, a determination may
be made as to whether or not the detected area is an area including
available parking spaces, via communication with the outside of the
vehicle, that is, via so-called road-to-vehicle communication or
vehicle-to-vehicle communication.
[0039] When a determination is made that the subject vehicle is
traveling in a parking area, the control device 10 detects white
lines on the basis of the captured images acquired for generation
of an overhead image. White lines represent boundary lines that
define frames (regions) of parking spaces. The control device 10
performs edge detection on the captured images to calculate a
luminance difference (contrast). The control device 10 specifies a
pixel line having a luminance difference of a predetermined value
or more from the overhead image and calculates the width and length
of the line. The control device 10 also detects whether or not
there are candidates of parking frame lines that have a higher
possibility of being lines of parking frames than the specified
line, around the portion in which the line is specified. For
example, when a line having a larger luminance difference is newly
specified, the newly specified line is detected as a line having a
higher possibility of representing a parking frame line. In the
present embodiment, frame lines representing parking spaces are not
necessarily white, and other colors such as red may also be
employed.
[0040] The ROM 12 of the control device 10 preliminarily stores
information on the patterns of parking frames. The patterns of
parking frames represent various shapes of parking spaces. For
example, in the parking spaces of FIG. 6A which will be described
later, the pattern of a parking frame is composed of three sides
among the sides which form a rectangle. Examples of parking frame
patterns include those for parallel parking as illustrated in FIG.
6B, which will be described later, and those for oblique-parking as
illustrated in FIG. 6C, which will also be described later.
[0041] The control device 10 specifies lines located on the road
surface from the overview image as candidates of parking frame
lines using a known image processing technique such as pattern
matching. When the specified candidates of parking frame lines
satisfy all of the following three conditions (1) to (3), the
control device 10 specifies the specified parking frame lines as
those representing parking spaces. The following conditions are
merely examples.
[0042] (1) Lines extracted as candidates of parking frame lines do
not include a line having a length equal to or larger than a first
line length threshold that is preliminarily set (e.g. a length
corresponding to an actual distance of 15 [m]).
[0043] (2) Among lines extracted as candidates of parking frame
lines, a set of adjacent two lines within a first line spacing
range that is preliminarily set (e.g. a length corresponding to an
actual distance of 3 to 5 [m]) does not include a set of lines
having a length equal to or smaller than a second line length
threshold that is preliminarily set (e.g. a length corresponding to
an actual distance of 7 [m]).
[0044] (3) Among lines extracted as candidates of parking frame
lines, a set of adjacent two lines within a second line spacing
range that is preliminarily set (e.g. a length corresponding to an
actual distance of 2.5 to 5 [m]) does not include a set of lines
having a length equal to or smaller than a third line length
threshold that is preliminarily set (e.g. a length corresponding to
an actual distance of 15 [m]).
[0045] In case of specifying parking spaces that satisfy the above
three conditions, the control device 10 determines whether or not
obstacles are present in the specified parking spaces using the
detection data from the ranging device 3. In addition, the control
device 10 determines whether or not the specified parking spaces
are those into which parking is possible by automated driving, on
the basis of a travel route in the automated driving. For example,
parking spaces for which a travel route in the automated driving
cannot be ensured, such as parking spaces facing a wall, do not
correspond to parking spaces into which parking is possible by the
automated driving. Then, the control device 10 detects parking
spaces, from among the specified parking spaces, in which obstacles
do not exist and into which parking is possible by the automated
driving, as the available parking spaces Me. Thus, the control
device 10 detects the available parking spaces Me. In the above
description, the control device 10 detects the available parking
spaces while detecting parking frame lines, but the parking frame
lines may not necessarily be detected to detect the available
parking spaces. In addition or alternatively, the control device 10
may detect empty spaces having a certain range and detect the empty
spaces as the available parking spaces and may also detect the
available parking spaces using information about past results of
parking. In addition or alternatively, when parking spaces satisfy
a predetermined condition, the control device 10 may detect the
parking spaces satisfying the predetermined condition as the
available parking spaces.
[0046] FIG. 4A is a first view for describing an example of the
parking assist process according to the present embodiment. It is
assumed that, in FIG. 4A, the position of the subject vehicle
traveling is P1 and the vehicle speed is V1. Arrows L represent a
travel route when the vehicle is parked by automated driving.
Dotted circles represent the available parking spaces Me detected
at the position P1.
[0047] In FIG. 4A and in FIGS. 4B to 4D which will be described
later, the movement of the subject vehicle is represented in a
temporal sequence, and the position of the subject vehicle moves
from FIG. 4A in the order of FIG. 4B, FIG. 4C, and FIG. 4D. FIG.
4E, which will be described later, is not continuous with FIGS. 4A
to 4D in the temporal sequence.
[0048] The travel route L is a route on which the subject vehicle
moves from the current position G1 to an intermediate position Mw
located ahead of the subject vehicle and reverses to complete the
parking maneuver into an available parking space PL. Such parking
maneuver includes one or more turns for parking. In FIG. 4A, an
obstacle M1 exists on the parking space PR8, and the control device
10 therefore does not detect the parking space PR8 as an available
parking space Me. With regard to the parking space PL8, a travel
route cannot be ensured in the automated driving because a wall Wa
interferes with the travel route (corresponding to dotted arrows in
FIG. 4A), and the parking space PL8 is therefore not a parking
space suitable for the automated driving. Accordingly, the control
device 10 does not detect the parking space PR 8 as an available
parking space Me. Other vehicles are parked in the parking spaces
PR1, PR4, PR6, and PL3, and the control device 10 therefore does
not detect them as available parking spaces Me. The control device
10 detects the parking spaces PL1, PL2, PL4 to PL7, PR2, PR3, PR5,
and PR7 as available parking spaces Me.
[0049] The control apparatus 10 sets a range that includes the
parking spaces PL2 to PL5 and PR2 to PR5, among the parking spaces
included in the images captured at the position P1 of the subject
vehicle, as the detection range for available parking spaces Me.
The detection range for available parking spaces Me during the
vehicle's travel is not limited to the range of parking spaces PL2
to PL5 and PR2 to PR5, and may also be the range of parking spaces
PL1 to PL8 and PR1 to PR8, for example.
[0050] Referring again to FIG. 2, in step 104, a recommended
available parking space Mr is detected. The recommended available
parking space Mr is an available parking space suitable for parking
the subject vehicle. The control device 10 detects the recommended
available parking space Mr in accordance with the traveling state
of the subject vehicle from among the detected plurality of
available parking spaces. The control device 10 stores the "parking
recommendation condition" for extracting the recommended available
parking space Mr. The "parking recommendation condition" is defined
from the viewpoint of extracting a parking space with which a
parking-related cost required for parking is low. The "parking
recommendation condition" is preferably defined from the viewpoint
of a time required for parking (required time for parking). On the
basis of the "parking recommendation condition," the control device
10 extracts the recommended available parking space Mr, with which
the parking-related cost is low, from among the available parking
spaces.
[0051] A method of detecting the recommended available parking
space Mr will be described below. The control device 10 evaluates
the parking-related cost required for parking into each available
parking space. The travel route used for evaluation of the cost is
a route from the start position at which the parking assist process
(automated driving) is started to the position of each available
parking space Me. The control device 10 calculates the travel route
when parking the subject vehicle into each available parking space
Me. The control device 10 sets the start position for each
available parking space Me. The control device 10 calculates a
travel route from the start position to each available parking
space Me. The number of travel routes for the automated driving is
not limited to one, and the control device 10 may calculate a
plurality of travel routes in accordance with the surrounding
situations.
[0052] The parking-related cost for parking into each available
parking space Me reflects a load such as the required time for
parking which is required for moving the subject vehicle to the
parking space by the automated driving.
[0053] The parking-related cost reflects a travel time for the
subject vehicle to be parked into an available parking space Me by
the automated driving and is obtained in accordance with the
required time for parking. The required time for parking is a time
when traveling by the automated driving along the travel route
calculated for each available parking space Me. The parking-related
cost may be obtained in accordance with the ease of entry into an
available parking space Me. The ease of entry into an available
parking space Me is determined in accordance with the travel
distance, the number of operations (the number of turns for
parking), the maximum steering angle, the vehicle speed, etc. For
example, when the travel distance is long, when the number of turns
for parking is large, when the maximum steering angle is large,
and/or when the vehicle speed is high, it is not easy to enter an
available parking space Me, and the parking-related cost is high.
In other words, the ease of entry is evaluated for each available
parking space, and on the assumption that an available parking
space into which entry is easiest is the available parking space
with which the parking-related cost is smallest, the available
parking space may be set as the recommended available parking
space. Factors of the parking-related cost may include not only the
required time for parking but also other factors such as the
certainty of parking in the automated driving. The parking-related
cost may not necessarily be an index equivalent to the required
time for parking and may also be calculated from the relative
relationship with the number of turns for parking on a travel
route, the length of a travel route, or the maximum steering angle.
The parking-related cost may be calculated on the basis of each
index, such as the required time for parking, the ease of entry
into an available parking space Me, and the certainty of parking,
or on the basis of a combination of two or more indices, or on the
basis of a combination of all the indices.
[0054] In the following description of the present embodiment, the
parking-related cost is calculated on the basis of the required
time for parking. The travel route is different for each available
parking space Me in accordance with the number of turns for
parking, the travel distance, the maximum steering angle, etc. When
the vehicle travels along a travel route by the automated driving,
therefore, the required time for parking is different for each
travel route. For example, the required time for parking will be
shorter as the number of turns for parking is smaller, as the
distance of a travel route is shorter, or as the maximum steering
angle is smaller. As illustrated in FIG. 4A, on the assumption of
parking into the available parking space PL6 or PL7, the distance
from the vicinity of the parking space PL7 to the wall Wa is
shorter than the distance from the vicinity of the parking space
PL6 to the wall Wa. The number of turns for parking when parking
into the parking space PL7 is therefore larger than the number of
turns for parking when parking into the parking space PL6, and the
required time for parking into the parking space PL7 is longer than
the required time for parking into the parking space PL6 (the
parking-related cost is higher in the former case).
[0055] The control device 10 then calculates a gaze point distance
on the basis of the vehicle speed of the subject vehicle. The gaze
point distance refers to a distance from the position of the
subject vehicle to the position which the driver of the subject
vehicle gazes on. In general, the higher the vehicle speed, the
farther the driver gazes on, and the lower the vehicle speed, the
closer the driver gazes on. From the viewpoint of recommending an
available parking space in accordance with the observing point of
the driver, the control device 10 sets a longer gaze point distance
as the vehicle speed of the subject vehicle is higher, and sets a
shorter gaze point distance as the vehicle speed of the subject
vehicle is lower. This allows the parking assist into the available
parking space to be executed in accordance with the intention of
the driver. The gaze point distance does not have to be linear and
may also be defined along a curve. When the gaze point distance is
defined along a curve, the curvature of the curve may be associated
with the steering angle.
[0056] FIG. 5 is a graph illustrating the relationship between the
vehicle speed (V [km/s]) and the gaze point distance (Y [m]). The
solid line represents a characteristic when the vehicle speed
increases while the broken line represents a characteristic when
the vehicle speed decreases. As illustrated in FIG. 5, when the
vehicle speed is Va or lower, the gaze point distance is Ya. When
the vehicle speed increases from Va to Vc, the gaze point distance
maintains Ya. Then, as the vehicle speed increases from the state
of Vc, the gaze point distance increases in proportion to the
vehicle speed within a range of Vc or higher and Vd or lower of the
vehicle speed. When the vehicle speed is Vd or higher, the gaze
point distance maintains Yb. On the other hand, when the vehicle
speed lowers from the state of Vd, the gaze point distance
maintains Yb until the vehicle speed returns to Vb from Vd. The
gaze point distance decreases in proportion to the vehicle speed
within a range of Va or higher and Vc or lower of the vehicle
speed. Thus, the relationship between the vehicle speed and the
gaze point distance has a hysteresis characteristic between the
increasing direction and decreasing direction of the vehicle
speed.
[0057] The ROM 12 of the control device 10 stores the relationship
between the vehicle speed and the gaze point distance as a map.
When acquiring the information on the vehicle speed from the
vehicle speed sensor 60, the control device 10 refers to the map to
calculate the gaze point distance corresponding to the vehicle
speed.
[0058] FIG. 4B illustrates a state in which the subject vehicle
moves forward from the position P1 illustrated in FIG. 4A to a
position P2. The speed of the subject vehicle at the position P2 is
V2 (<V1). The control device 10 refers to the map to calculate
the gaze point distance corresponding to the vehicle speed V2. The
control device 10 specifies a point G2 that is separate from the
position P2 by the gaze point distance, as a gaze point (G2). The
subject vehicle is in a state of selecting an available parking
space with the lowered vehicle speed V2 (<V1). The distance
between the gaze point G2 and the subject vehicle is shorter than
the distance between the gaze point G1 illustrated in FIG. 4A and
the subject vehicle because the vehicle speed is lowered.
[0059] In the state illustrated in FIG. 4B, the control device 10
detects a recommended available parking space from among the
available parking spaces PL2, PL4, PL5, PR2, PR3, and PR5 in the
vicinity of the gaze point G2. The control device 10 detects the
recommended available parking space on the basis of the
parking-related cost for each of the parking spaces PL2, PL4, PL5,
PR2, PR3, and PR5.
[0060] The control device 10 then assigns numbers for
identification to the available parking spaces Me in the vicinity
of the gaze point G2. For example, the identification numbers are
given in the order of proximity to the gaze point G2. The control
device 10 calculates the parking-related cost for parking into each
available parking space Me (the parking-related cost represents an
index of the ease of entry into each available parking space Me).
The control device 10 may read out the parking-related cost for
parking which is previously calculated.
[0061] To evaluate the parking-related cost, the control device 10
calculates the required time for parking into each available
parking space Me. In the example of FIG. 4B, the control device 10
calculates the parking-related cost (required time for parking) for
each of the available parking spaces PL2, PL4, PL5, PR2, PR3, and
PR5 and stores the parking-related cost such that it is associated
with each identification number.
[0062] The control device 10 compares the required time for parking
into each available parking space Me with a predetermined required
time threshold. The required time threshold is a value that is
preliminarily set and an upper limit of the required time when
parking by the automated driving. When the required time for
parking into an available parking space Me is longer than the
required time threshold, the control device 10 does not detect the
available parking space Me as the recommended available parking
space Mr.
[0063] After detecting the available parking spaces Me with which
the required time for parking is shorter than the required time
threshold, the control device 10 sets an available parking space Me
that is closest to the gaze point among the detected available
parking spaces Me as the recommended available parking space Mr. In
the example of FIG. 4B, the required time for parking into the
parking space PL4 is shorter than the required time threshold, and
the parking space PL4 is located closest to the gaze point. The
control device 10 therefore sets the parking space PL4 as the
recommended available parking space Mr. In the above-described
embodiment, among the available parking spaces Me with which the
required time for parking is shorter than the required time
threshold, the available parking space with the shortest gaze point
distance is set as the recommended available parking space Mr, but
another method may be employed to set the recommended available
parking space Mr. For example, among the available parking spaces
Me with which the required time for parking is shorter than the
required time threshold, an available parking space Me with which
the required time for parking is shortest may be set as the
recommended available parking space Mr. In another embodiment, for
example, it is assumed that, in the detection of the recommended
available parking space Mr, available parking spaces Me can be set
as the recommended available parking space Mr when the gaze point
distance from the gaze point to the available parking space Me is
within a predetermined distance. From among such available parking
spaces Me, an available parking space with which the required time
for parking is shortest may be detected as the recommended
available parking space Mr.
[0064] As described above, in the present embodiment, the gaze
point distance is calculated on the basis of the vehicle speed, and
a position separate from the current position of the subject
vehicle by the gaze point distance is specified as the gaze point.
Further, among the available parking spaces, an available parking
space closest to the gaze point is set as the recommended available
parking space Mr. That is, the gaze point distance based on the
vehicle speed is calculated to specify the gaze point of the user,
thereby specifying the recommended available parking space with
consideration for the intention of the user (driving operation by
the user). In the present embodiment, the parking-related cost is
calculated for each available parking space, and among the
available parking spaces, an available parking space with which the
parking-related cost is low is set as the recommended available
parking space Mr. That is, cost evaluation is employed to determine
the state of the vehicle in the automated driving before the
automated driving is executed, and the recommended available
parking space is specified. Through this operation, in the present
embodiment, an available parking space suitable for parking the
subject vehicle is set as the recommended available parking space
in accordance with the traveling state of the subject vehicle.
[0065] The control device 10 executes the detection process for the
recommended available parking space Mr at a predetermined period.
As illustrated in FIG. 4C, also when the subject vehicle moves
forward to the position P3 at a vehicle speed of V3, the control
device 10 detects a new recommended available parking space Mr. The
control device 10 calculates a new gaze point G3 and the
parking-related cost required for moving from the current position
to each available parking space Me and detects the parking space
PL5, with which the parking-related cost is lowest, as the
recommended available parking space Mr.
[0066] In step 105, the available parking spaces Me and the
recommended available parking space Mr are presented. The control
device 10 controls the display 21 to display the set available
parking spaces Me and the set recommended available parking space
Mr thereby to present them to the driver and passengers. The
display form on the display 21 will be described later.
[0067] In step 106, a determination is made as to whether or not a
target parking space Mo is input. The target parking space Mo is a
parking space into which the vehicle is parked by the automated
driving, and represents a location to be the target in the
automated driving. The target parking space Mo is set on the basis
of the operation by the driver or a passenger. For example, when
the display 21 is a touch panel-type display, the driver or a
passenger touches a portion representing a desired parking space
thereby to designate the target parking space Mo, and information
on the target parking space Mo is input to the control device
10.
[0068] When the target parking space Mo is input, the control flow
proceeds to step 107. On the other hand, when the target parking
space Mo is not input, the control flow returns to step 104, and
the control flow from step 104 to step 106 is repeatedly
executed.
[0069] When the target parking space Mo is input, this parking
space is set as the target parking space Mo in step S107.
[0070] In step 108, the control device 10 calculates a travel route
for moving the subject vehicle to the target parking space Mo.
[0071] FIG. 4D is a view illustrating a scene in which the
available parking space PL5 is designated as the target parking
space Mo. The control device 10 calculates a travel route for
parking on the basis of the positional relationship between the
position P4 of the subject vehicle at which the parking maneuver
(movement) is started (automated parking start position) and the
position of the target parking space Mo. Although not particularly
limited, the control device 10 calculates the travel route to
include two curves. The first curve lies from the stop position of
the subject vehicle, that is, the start position (P4) at which the
parking assist is started, to the turning position Mw at which the
turn for parking is performed. The second curve lies from the
turning position Mw to the target parking space Mo (PL5).
[0072] The control device 10 reads travel routes corresponding to
the selected parking mode and calculates a travel route on the
basis of the positional relationship between the position of the
subject vehicle when starting the automated parking process and the
position of the target parking space Mo. When the user presses the
previously-described deadman switch during the operation of the
automated parking mode, the control device 10 controls the vehicle
controller 30 to execute the process of moving the subject vehicle
to the target parking space Mo on the calculated travel route.
[0073] The control device 10 calculates the travel route
corresponding to each of right-angle parking, parallel parking, and
oblique parking illustrated in FIGS. 6A-6C, respectively. In the
present embodiment, the travel route has been described as being
calculated, but the present invention is not limited to this. In an
alternative embodiment, a travel route corresponding to the type of
the parking space is stored in a memory (ROM), and the travel route
may be read out when parking. The parking mode (such as right-angle
parking, parallel parking, and oblique parking) may be selected by
the driver of the subject vehicle.
[0074] In step 109, the parking assist apparatus 100 according to
the present embodiment executes the parking assist process or the
automated parking process. The parking assist apparatus 100
according to the present embodiment controls the operation of the
drive system 40 via the vehicle controller 30 so that the subject
vehicle moves along the travel route.
[0075] The parking assist apparatus 100 according to the present
embodiment includes a parking assist control unit. The parking
assist control unit acquires shift range information from an AT/CVT
control unit, wheel speed information from an ABS control unit,
steering angle information from a steering angle control unit,
engine speed information from an ECM, and other necessary
information. On the basis thereof, the parking assist control unit
calculates and outputs instruction information on the automated
steering to the EPS control unit, instruction information such as
warning to a meter control unit, etc. The control device 10
acquires information items, which are acquired by the steering
angle sensor 50 of the steering apparatus of the vehicle and the
vehicle speed sensor 60 and other sensors of the vehicle, via the
vehicle controller 30.
[0076] The drive system 40 according to the present embodiment
allows the subject vehicle to be parked into the target parking
space Mo by driving based on the control command signals acquired
from the parking assist apparatus 100. The steering apparatus
according to the present embodiment is a drive mechanism that moves
the subject vehicle in the right and left directions. The EPS motor
included in the drive system 40 drives the power steering mechanism
of the steering of the steering apparatus on the basis of the
control command signals acquired from the parking assist apparatus
100 to control the steering amount and assists the operation when
moving the subject vehicle to the target parking space Mo. The
content of the parking assist and the scheme of operation are not
particularly limited, and schemes known at the time of filing of
this application can be appropriately applied.
[0077] When the parking assist apparatus 100 according to the
present embodiment controls the subject vehicle to move to the
target parking space Mo along the travel route calculated based on
the position P4 of the subject vehicle and the position of the
target parking space Mo, the operation of the accelerator/brake is
automatically controlled on the basis of the designated control
vehicle speed (set vehicle speed), and the operation of the
steering apparatus is also automatically controlled in accordance
with the vehicle speed. The parking assist apparatus 100 calculates
command signals to the drive system 40 of the subject vehicle, such
as an EPS motor, while feeding back the output value of the
steering angle sensor 50 of the steering apparatus so that the
travel trajectory of the subject vehicle coincides with the
calculated travel route, and sends the command signals to the drive
system 40 or to the vehicle controller 30 which controls the drive
system 40. That is, during the parking assist according to the
present embodiment, the steering operation and the
accelerator/brake operation are automatically performed. It is also
possible to perform a parking process by remote control that
includes transmitting a setting command for the target parking
space Mo, a parking process start command, a parking suspension
command, etc. to the vehicle with no driver therein from the
outside and performing the parking.
[0078] As will be understood, it is also possible for the driver to
operate the accelerator/brake, and only the operation of the
steering apparatus is automated. In this case, the parking assist
apparatus 100 controls the drive system 40 on the basis of the set
vehicle speed which is preliminarily calculated so that the subject
vehicle follows the travel route to move, and controls the steering
apparatus of the vehicle on the basis of the set steering angle
which is also preliminarily calculated.
[0079] A method of presenting parking assist information in the
parking assist apparatus 100 according to the present embodiment
will be described below.
[0080] FIG. 7A is a first view for describing an example of a
display screen in the parking assist process according to the
present embodiment. FIG. 7B is a second view for describing an
example of a display screen in the parking assist process according
to the present embodiment. FIG. 7A illustrates a display screen
when the subject vehicle is traveling at the position P2 of FIG.
4B. FIG. 7B illustrates a display screen when the subject vehicle
is traveling at the position P3 of FIG. 4C. FIGS. 7A and 7B
represent the parking assist information displayed when searching
for a parking space into which the subject vehicle is parked. What
are illustrated in FIGS. 7A and 7B are situations in which the
subject vehicle searches for a parking space into which the subject
vehicle is parked, while moving along the arrows.
[0081] In the display screen of FIG. 7A, an image (of boundary
lines of parking spaces) that indicates the parking spaces PL2 to
PL5 and PR2 to PR5 is displayed on the left-side overhead image
(top view) 21A on the screen of the display 21. In the display
screen of FIG. 7B, an image (of boundary lines of parking spaces)
that indicates the parking spaces PL3 to PL6 and PR3 to PR6 is
displayed on the left-side overhead image (top view) 21A on the
screen of the display 21. The center of the overhead image (top
view) 21A is displayed with an icon of the subject vehicle
indicating the position of the subject vehicle. The monitoring
image (normal view) can be displayed as any of images captured by
different cameras 1a to 1d in accordance with the operation state
of the subject vehicle. Examples illustrated in FIGS. 7A and 7B are
each displayed as an image captured by the camera 1a which is
disposed on the front grill part of the subject vehicle. When the
subject vehicle moves back, the monitoring image may be displayed
as an image captured by the camera 1d which is disposed in the
vicinity of the rear bumper. The image 21C is an image for
messages. In these examples, the overhead image 21A and the
monitoring image 21B are simultaneously displayed on the display
21, but only the overhead image 21A may be displayed on the display
21, or only the monitoring image 21B may be displayed on the
display 21.
[0082] The overhead image 21A is displayed with the available
parking spaces Me and the recommended available parking space Mr.
In a scene in which the subject vehicle searches for a target
parking space while moving in the parking lot, the available
parking spaces Me and the recommended available parking space Mr
change as the subject vehicle moves. The parking assist apparatus
100 displays the available parking spaces Me and the recommended
available parking space Mr which are sequentially detected. The
parking assist apparatus 100 displays the available parking spaces
Me with parking available marks in a circular shape and displays
the recommended available parking space Mr with a recommendation
mark in a rectangular shape.
[0083] As illustrated in FIGS. 7A and 7B, when the subject vehicle
is moving, the available parking spaces Me and the recommended
available parking space Mr sequentially change as the subject
vehicle moves. When an available parking space Me or recommended
available parking space Mr changes, the parking assist apparatus
100 changes the position of the parking available mark or
recommendation mark and displays it.
[0084] Here, a display form of the recommended available parking
space Mr when the subject vehicle moves while decelerating will be
described. As described above, the control device 10 sets the
recommended available parking space Mr for the available parking
space Me which is closest to the gaze point. The gaze point
distance varies in accordance with the vehicle speed of the subject
vehicle.
[0085] The description will be made for a case in which the
characteristic of the gaze point distance when the vehicle speed
increases and the characteristic of the gaze point distance when
the vehicle speed decreases follow the characteristic illustrated
by the solid line of FIG. 5 rather than the hysteresis
characteristic as illustrated in FIG. 5. It is assumed that, in the
example of FIG. 4B, the recommended available parking space Mr set
when the vehicle speed is Vd is the available parking space PL5. In
such a case, as the vehicle speed becomes lower than Vd from the
state of Vd, the gaze point distance becomes shorter than Yb, and
the recommended available parking space Mr changes from the
available parking space PL5 to another available parking space PL4.
That is, despite the fact that the subject vehicle travels toward
the recommended available parking space Mr (PL5) which is set
before deceleration, the screen of the display 21 shows a movement
such that the frame of the recommended available parking space Mr
returns below on the screen (in the direction opposite to the
travel direction of the subject vehicle, i.e. in the negative
direction of the y-axis of FIG. 7A). To prevent such unnatural
movement of the recommended available parking space Mr, in the
present embodiment, hysteresis is given to the characteristic of
the gaze point distance with respect to the vehicle speed.
[0086] With the hysteresis characteristic, the gaze point distance
is maintained at Yb when the vehicle speed becomes lower than Vd
from the state of Vd. The recommended available parking space Mr
therefore remains at the position of the available parking space
PL5 or moves to the available parking space PL6 on the travel
direction side of the vehicle from the position of the available
parking space PL5. That is, among a first available parking space
(corresponding to the available parking space PL5 of FIG. 4A) and a
second available parking space (corresponding to the available
parking space PL4 of FIG. 4A) that are disposed side by side along
a direction parallel to the travel direction of the subject vehicle
(the y-axis direction of FIG. 7A), the first available parking
space farther from the subject vehicle than the second available
parking space is set as the recommended available parking space by
the control device 10. Then, in the state in which the vehicle
speed of the subject vehicle decreases, the control device 10
prohibits the recommended available parking space (corresponding to
the available parking space PL5 of FIG. 4A) from moving from the
first available parking space to the second available parking space
(corresponding to the available parking space PL4 of FIG. 4A) on
the display screen of the display 21. This can prevent the
unnatural movement of the recommended available parking space
Mr.
[0087] Next, in a display form of the recommended available parking
space Mr, hunting in the lateral direction (the positive and
negative directions of the x-axis of FIG. 7A) and control for
preventing such hunting will be described.
[0088] FIGS. 4E and 4F are views for describing an example of the
parking assist process according to the present embodiment. As
described above, the recommended available parking space Mr changes
its position on the display screen of the display 21 in accordance
with the position of the vehicle. For example, in the parking area
illustrated in FIG. 4E, it is assumed that the subject vehicle is
traveling between a row of parking spaces on the left side and a
row of parking spaces on the right side (the vicinity of the center
in the lateral direction is indicated by a dashed-two dotted line).
It is also assumed that, as illustrated in FIG. 4E, a number of
parking spaces are empty in the parking area. When the subject
vehicle is traveling on the left side of the center line indicated
by the dashed-two dotted line, the position of the gaze point is
located on the left side of the center line. On the other hand,
when the subject vehicle is traveling on the right side of the
center line indicated by the dashed-two dotted line, the position
of the gaze point is located on the right side of the center line.
Accordingly, when the subject vehicle travels in the vicinity of
the center in the lateral direction with respect to the direction
in which the parking spaces are arranged, the position of the
subject vehicle may swing laterally across the center line, and the
position of the gaze point will also swing laterally. If the
available parking space Me closest to the gaze point is set as the
recommended available parking space Mr, the displayed frame of the
recommended available parking space Mr will frequently move right
and left. In the present embodiment, control is executed as below
to prevent such hunting of the recommended available parking space
Mr.
[0089] The control device 10 sets a fixed display mode for fixing
the display region for the recommended available parking space Mr
in accordance with the number of the available parking spaces Me.
In the fixed display mode, the region in which the recommended
available parking space Mr can be set is fixed to any of the left
side and the right side. The control device 10 compares the number
of the available parking spaces Me with a predetermined value. When
the number of the available parking spaces Me is not smaller than
the predetermined value, the control device 10 sets the display
mode to the fixed display mode.
[0090] When the fixed display mode is set, the control device 10
selects one of right and left regions as a settable region for the
recommended available parking space Mr in accordance with the
traveling state of the subject vehicle. When the settable region is
set, the control device 10 sets the recommended available parking
space among the available parking spaces included in the settable
region. The control device 10 calculates the distances from the
parking spaces located on the sides of the subject vehicle to the
subject vehicle as lateral distances (XL, XR). In the examples of
FIGS. 4E and 4F, XL represents the lateral distance on the left
side and XR represents the lateral distance on the right side. The
control device 10 compares XL with XR. When XL is shorter than XR,
the control device 10 sets the region on the left side as the
settable region for the recommended available parking space Mr.
When XR is shorter than XL, the control device 10 sets the region
on the right side as the settable region for the recommended
available parking space Mr.
[0091] After setting the settable region for the recommended
available parking space Mr to the right or left, the control device
10 adds a length XHIS to a length (W/2). The length (W/2) is a
length obtained by halving the length of the lateral distance
between the left-side parking spaces and the right-side parking
spaces. The length XHIS is a length that defines a bias. When the
left-side region is set as the settable region for the recommended
available parking space Mr, the control device 10 compares the
left-side lateral distance XL with a length (XHIS+W/2) to which the
bias XHIS is added. When the left-side lateral distance XL is
longer than the length (XHIS+W/2), the control device 10 changes
the settable region for the recommended available parking space Mr
from the left-side region to the right-side region. When the
left-side lateral distance XL is not longer than the length
(XHIS+W/2), the control device 10 maintains the state in which the
left-side region is set as the settable region for the recommended
available parking space Mr.
[0092] As illustrated in FIG. 4E, after the settable region for the
recommended available parking space Mr is set to the left side,
when the left-side lateral distance XL is not longer than the
length (XHIS+W/2), the control device 10 maintains the state in
which the settable region for the recommended available parking
space Mr is set at the left side. On the other hand, as illustrated
in FIG. 4F, after the settable region for the recommended available
parking space Mr is set to the left side, when the subject vehicle
travels on the right side of the center line and the left-side
lateral distance XL is longer than the length (XHIS+W/2), the
control device 10 changes the settable region for the recommended
available parking space Mr from the left-side region to the
right-side region. Through this operation, selection between the
right side and the left side when set as the settable region can
have a hysteresis characteristic with respect to the lateral
position of the subject vehicle. For example, when the left-side
region is set as the settable region for the recommended available
parking space Mr, the recommended available parking space Mr is
preferentially displayed on the left-side region as compared with
the right side. This makes it possible to suppress the occurrence
of hunting of the recommended available parking space Mr on the
display screen of the display 21. In the above description, the
left-side region is set as the settable region for the recommended
available parking space Mr and the settable region for the
recommended available parking space Mr is changed in accordance
with the comparison result between the lateral distance (XL) of the
subject vehicle and the length (XHIS+W/2), but when the right-side
region is set as the settable region for the recommended available
parking space Mr, the settable region for the recommended available
parking space Mr may be changed in accordance with the comparison
result between the lateral distance (XR) of the subject vehicle and
the length (XHIS+W/2).
[0093] When the number of the available parking spaces Me is less
than the predetermined value, the control device 10 sets the
display mode to a normal mode. In the normal mode, no settable
region is set. When the parking area includes few empty parking
spaces, prompt presentation of the empty parking spaces to the
driver and passengers may be more important than preventing the
hunting. Thus, the convenience of the system for the driver and
passengers can be improved.
[0094] When the subject vehicle stops from the state of moving as
illustrated in FIGS. 7A and 7B, the display screen of the display
21 becomes a screen as illustrated in FIG. 7C. FIG. 7C is a third
view for describing an example of a display screen in the parking
assist process according to the present embodiment. The display
screen of FIG. 7C is a display screen when the vehicle stops at the
position P3 in FIG. 4C.
[0095] As illustrated in the display screen of FIG. 7C, the user
finds the messages included in the image 21C and can confirm that
selection and input of the target parking space Mo are required.
The user designates the available parking space PL5, which is
presented as the recommended available parking space Mr, as the
target parking space Mo. The user touches the available parking
space PL5, which is displayed on the touch panel-type display 21,
thereby to designate this available parking space as the target
parking space Mo. The display screen of the display is changed from
the display screen of FIG. 7C to the display screen of FIG. 7D.
[0096] FIG. 7D is a fourth view for describing an example of a
display screen in the parking assist process according to the
present embodiment. The display screen of FIG. 7D is a display
screen when the vehicle stops at the position P4 in FIG. 4D.
[0097] The control device 10 controls the display 21 to display the
display screen as illustrated in FIG. 7D thereby to present the
target parking space Mo to the driver and passengers. The driver
and passengers find the messages included in the image 21C and can
confirm that the automated driving can be started.
[0098] FIG. 7E is a fifth view for describing an example of a
display screen in the parking assist process according to the
present embodiment. When the automated driving is started, the
display screen of the display 21 becomes a screen as illustrated in
FIG. 7E, and the subject vehicle moves forward. At this time, the
image 21C is displayed with messages informing that the subject
vehicle is moving forward by the automated driving and that the
driver and passengers should gaze around the subject vehicle.
[0099] In the present embodiment, a determination may be made as to
whether or not the subject vehicle decelerates, and when the
recommended available parking space is displayed in a state in
which the subject vehicle decelerates, the recommended available
parking space may be prohibited from changing to another available
parking space. In general, the case in which a vehicle decelerates
in the vicinity of the parking space may often be a case in which
the driver or passenger determines the recommended available
parking space as the target parking space and starts parking. If,
at that time, the recommended available parking space changes, it
will be difficult for the driver or passenger to select the
recommended available parking space into which the driver or
passenger intends to park. Thus, the recommended available parking
space is prohibited from changing to another available parking
space, and the recommended available parking space into which the
driver or passenger intends to park can thereby be maintained and
displayed.
[0100] As described above, according to the present embodiment,
available parking spaces are detected, a recommended available
parking space is set among the detected available parking spaces in
accordance with the traveling state of the subject vehicle, and the
set recommended available parking space is displayed on the display
21. Through this operation, an available parking space suitable for
the automated driving can be presented to the driver and
passengers.
[0101] According to the present embodiment, the required time for
parking when the subject vehicle is parked into each of the
available parking spaces is calculated, and among the available
parking spaces, an available parking space with which the required
time for parking is shorter than a predetermined time is set as the
recommended available parking space. Through this operation, an
available parking space with which the required time for parking is
short can be presented to the driver and passengers.
[0102] According to the present embodiment, the required time for
parking when the subject vehicle is parked into each of the
available parking spaces is calculated, and among the available
parking spaces, an available parking space with which the required
time for parking is shortest is set as the recommended available
parking space. Through this operation, the available parking space
with which the required time for parking is shortest can be
presented to the driver and passengers.
[0103] According to the present embodiment, a position separate
from the subject vehicle by a given gaze point distance is
specified as a gaze point, and among the available parking spaces,
an available parking space with which the distance from the gaze
point to the available parking space is shorter than a
predetermined distance threshold is set as the recommended
available parking space. Through this operation, an available
parking space suitable for the automated driving can be presented
to the driver and passengers while reflecting the intention of the
user.
[0104] According to the present embodiment, a position separate
from the subject vehicle by a given gaze point distance is
specified as a gaze point, and among the available parking spaces,
an available parking space with which the distance from the gaze
point to the available parking space is shortest is set as the
recommended available parking space. Through this operation, an
available parking space suitable for the automated driving can be
presented to the driver and passengers while reflecting the
intention of the user.
[0105] According to the present embodiment, the ease of entry when
the subject vehicle is parked into each of the available parking
spaces by the automated driving is evaluated, and among the
available parking spaces, an available parking space into which
entry is easiest is set as the recommended available parking space.
Through this operation the available parking space into which the
entry is easiest can be presented to the driver and passengers.
[0106] According to the present embodiment, among a first available
parking space and a second available parking space that are
disposed side by side along a direction parallel to the travel
direction of the subject vehicle, the first available parking space
farther from the subject vehicle than the second available parking
space is set as the recommended available parking space. In a state
in which the vehicle speed of the subject vehicle decreases, the
recommended available parking space is prohibited from moving from
the first available parking space to the second available parking
space on the display screen of the display 21. Through this
operation, unnatural movement of the recommended available parking
space Mr can be prevented.
[0107] According to the present embodiment, when the recommended
available parking space is displayed in a state in which the
subject vehicle decelerates, the recommended available parking
space is prohibited from changing to another available parking
space. Through this operation, the recommended available parking
space can be maintained and displayed while making aware of the
driver's intention (passengers' intention) of parking.
[0108] According to the present embodiment, when parking spaces are
present at the right and left with respect to the travel direction
of the subject vehicle, one of the right and left regions is set as
a settable region for the recommended available parking space in
accordance with the traveling state of the subject vehicle, and a
parking space included in the settable region is set as the
recommended available parking space. This can suppress a phenomenon
that the frame of the recommended available parking space is
repeatedly displayed at the right and left on the display screen of
the display 21 (hunting).
[0109] According to the present embodiment, the distance from the
parking space located on a side of the subject vehicle to the
subject vehicle is calculated as a lateral distance, and one of the
right and left regions is set as the settable region for the
recommended available parking space in accordance with the length
of the lateral distance. The characteristic when one of the right
and left regions is selected is a hysteresis characteristic with
respect to the length of the lateral distance. This can suppress a
phenomenon that the frame of the recommended available parking
space is repeatedly displayed at the right and left on the display
screen of the display 21 (hunting).
[0110] According to the present embodiment, when a predetermined
number or more of the available parking spaces are present, an
available parking space located at one of the right and left is set
as the recommended available parking space in accordance with the
traveling situation of the subject vehicle. This can suppress a
phenomenon that the frame of the recommended available parking
space is repeatedly displayed at the right and left on the display
screen of the display 21 (hunting).
[0111] In the present embodiment, the number of recommended
available parking spaces set by the control device 10 is not
limited to one and may be two or more. The number of recommended
available parking spaces displayed on the display 21 is also not
limited to one and may be two or more.
[0112] In the present embodiment, to prevent the display screen of
the display 21 from showing an unnatural movement such that the
frame of the recommended available parking space Mr returns below
on the screen, a hysteresis characteristic is given to the
relationship between the vehicle speed and the gaze point distance,
but the control may be modified as below. As illustrated in FIG.
4C, the control device 10 sets the available parking space PL5 as
the recommended available parking space and controls the display 21
to display the recommended available parking space. As the subject
vehicle decelerates, the control device 10 sets the available
parking space PL4 as the recommended available parking space. The
control device 10 controls the display 21 to continue to display
the available parking space PL5 as the recommended available
parking space rather than displaying the set available parking
space PL4. That is, in the setting control for the recommended
available parking space, even when the position of an available
parking space relatively moves in the direction of approaching the
subject vehicle due to decrease of the vehicle speed, the display
position of the recommended available parking space is fixed on the
display screen of the display 21. This can prevent the unnatural
movement of the recommended available parking space Mr.
[0113] In the present embodiment, the available parking space Me
closest to the gaze point is set as the recommended available
parking space Mr, but the available parking space Me with which the
distance from the gaze point to the available parking space Me is
shorter than a predetermined distance threshold may be set as the
recommended available parking space Mr. When there is a plurality
of recommended available parking spaces Mr that can be set in
accordance with the distances from the gaze point to the available
parking spaces Me, an available parking space with which the
parking-related cost is low may be set as the recommended available
parking space Mr.
Second Embodiment
[0114] The parking assist system according to another embodiment of
the present invention will be described. This embodiment is
different from the above-described first embodiment in that the
length of the gaze point distance is changed in accordance with the
travel direction of the subject vehicle. Other configuration is the
same as that of the first embodiment, and the description is
borrowed herein.
[0115] FIGS. 8A-8B are a set of views for describing an example of
the parking assist process according to the present embodiment.
FIG. 8A illustrates a view when the subject vehicle is parked into
the target parking space Mo from a state in which the subject
vehicle is traveling forward (forward state). FIG. 8B illustrates a
view when the subject vehicle is parked into the target parking
space Mo from a state in which the subject vehicle is traveling
backward (backward state).
[0116] In FIG. 8A, it is assumed that the current position of the
subject vehicle is P6, the gaze point when the position of the
subject vehicle is P6 is G6, and the turning point is P7. In FIG.
8B, it is assumed that the gaze point when the position of the
subject vehicle is P6 is Gb. The gaze point Ga is a gaze point when
set from the same gaze point distance as that in the forward
state.
[0117] In a state in which the subject vehicle is traveling forward
as illustrated in FIG. 8A, when the subject vehicle is parked into
the available parking space PL5 in the backward parking (a parking
state in which the subject vehicle can move forward to exit from
the available parking space), the subject vehicle stops in the
vicinity of the gaze point, then moves forward to the turning point
P7, turns for parking at the point P7, moves backward to the
available parking space PL5, and parks into the available parking
space PL5. On the other hand, in a state in which the subject
vehicle is traveling backward as illustrated in FIG. 8B, when the
subject vehicle is parked into the available parking space PL5 in
the backward parking, the subject vehicle stops at the start
position of the automated driving and then moves backward from the
start position of the automated driving to the available parking
space PL5 to park into the available parking space PL5 without
turning for parking.
[0118] When the subject vehicle is traveling forward, the distance
between the start position of the automated driving and the target
parking space Mo is short. On the other hand, when the subject
vehicle is traveling backward, the distance between the start
position of the automated driving and the target parking space Mo
is longer than that when the subject vehicle is traveling forward
because the subject vehicle does not turn for parking.
[0119] FIG. 9 is a graph illustrating a relationship between the
vehicle speed (V [km]) and the gaze point distance (Y [m]). The
solid line indicates a characteristic in the backward state while
the dotted line indicates a characteristic in the forward state. In
the forward state, when the vehicle speed is lower than Vc, the
gaze point distance is Ya. When the vehicle speed is within a range
of Vc or higher and lower than Vd, the gaze point distance
increases in proportion to the vehicle speed. When the vehicle
speed is not lower than Vd, the gaze point distance is Yb. In the
backward state, when the vehicle speed is lower than Ve
(Vc<Ve<Vd), the gaze point distance is Yc (Ya<Yc<Yb).
When the vehicle speed is within a range of Ve or higher and lower
than Vd, the gaze point distance increases in proportion to the
vehicle speed. When the vehicle speed is not lower than Vd, the
gaze point distance is Yb. The gaze point distance Yc is
preliminarily set in accordance with the length of the travel route
when the automated operation is performed from the state in which
the vehicle moves backward.
[0120] As illustrated in FIG. 9, when the vehicle speed becomes
lower than Ve in a state in which the subject vehicle is traveling
backward, the gaze point distance is set to Yc which is longer than
the gaze point distance (Ya) in the forward state. The gaze point
(corresponding to the start position of the automated driving)
located behind the subject vehicle is therefore set to be far. The
recommended available parking space set in the vicinity of the gaze
point is set at a position separate from the subject vehicle
accordingly. That is, in the present embodiment, an appropriate
length of the gaze point distance can be set to match each of the
travel route when parking by the automated driving from the forward
state and the travel route when parking by the automated driving
from the backward state.
[0121] As described above, according to the present embodiment, the
length of the gaze point distance is set in accordance with whether
the travel direction of the subject vehicle is forward or backward.
Through this operation, a parking space suitable for the automated
driving can be presented to the driver and passenger in accordance
with the travel direction of the subject vehicle in the parking
area.
REFERENCE SIGNS LIST
[0122] 1000 Parking assist system
[0123] 100 Parking assist apparatus [0124] 10 Control device [0125]
11 CPU [0126] 12 ROM [0127] 13 RAM
[0128] 20 Output device [0129] 21 Display [0130] 22 Speaker [0131]
23 Lamp
[0132] 1a-1d On-board cameras
[0133] 2 Image processing device
[0134] 3 Ranging device
[0135] 30 Vehicle controller
[0136] 40 Drive system
[0137] 50 Steering angle sensor
[0138] 60 Vehicle speed sensor [0139] V Vehicle [0140] Me Available
parking space [0141] Mr Recommended available parking space [0142]
Mo Target parking space
* * * * *